Construction of hermetically sealed tank



3 United States Patent 3,176,876 4/1965 Fischeretal. 251/368 3 12/1966 Adams 126/113 Primary Examiner-William F. ODea [72] Inventor CharlesA.Adams 614 Taylor St., Davenport, lowa 52802 [21] Appl. No. 638,931 g filled d i 3g Assistant Examiner-David R. Matthews [4 1 meme c AttorneyWilliam A. Murray [54] CONSTRUCTION OF HERMETICALLY SEALED TANK mammssnrawmg Flgs' ABSTRACT: A hermetically sealed tank for use with a hu- [52] U.S. 137/391, mldifier composed ofa base with an outer inclined peripheral rim; a downwardly opening container with a lower edge beara central upright tube extending through the base and having an upper end adjacent the top of the container and a lower end with a radial shoulder bearing against the upper end being threadedly atner whereby adjusting the threaded attachment may tighten or loosen the seal between the lower e .1 ef .m m -l f m W t. m a n... .m mm we m a U g Cc .m mm

and mechanical means supported on the base for closing the outlet and edge and rim; a fluid inlet and outlet in the base;

opening the inlet at one position, and for closing the inlet and opening the outlet at a second position.

a e m ullpn i I Ir Patented Oct. 6, 1970 3,532,112

3 3 l :22;- IE' 1' 70 1,1 2s I R I 20 v 2 2 i. I

z *3 38 i I I I 1 4O 32 I2 22 I :21 i 3| 3 A A E 42 4| 34 INVENTOR. I CHARLES A. ADAMS ATTORNEY CONSTRUCTION OF HERMETICALLY SEALED TANK BACKGROUND OF THE INVENTION there is shown and described a humidifier having a hermeti- I cally sealed tank that is dependent upon vacuum to retain the water in the tank and which discharges water into a humidifier pan as the vacuum is relieved. The vacuum is controlled by a pipe that extends through the base and depends into the water in the pan and opens also at the top of the tank. A water outlet valve is provided at the base of the tank and is normally opened. Consequently, as water is evaporated in the humidifier pan the level will fall below the lower end of the pipe. The vacuum is relieved at the top of the tank and water is discharged through the outlet until the level in the pan is above the lower end, at which time a vacuum is again established. There is also provided in the tank means that includes a float and mechanism that open a water inlet valve and close the discharge valve as the water level in the tank approaches the base in order to fill the tank and to close the inlet valve and open the outlet valve as the tankis again filled.

In the above structure, the tank or container opens downwardly and is sealed by a large O-ring between a horizontal flange on the tank and the surface of a base plate. This is not satisfactory for the reason that should repair work be required, the O-ring after some use, needs replacement upon the tank being reassembled. Often, due to the large size of the ring, a replacement is not available and the old one must be reused with the possibility of leaks occurring. Also, the tank is bolted to the base plate at various places around its circumference, thereby requiring tightening at equal pressure on the bolts to prevent leakage. Further, the various valve housings are welded to the base, thereby creating sources of leakage at the welded joints. Also, such a construction is initially expensive and can price the humidifier out of the market.

SUMMARY With the above in mind, it is the primary object of the present invention to provide a unique tank structure that has no sealing ring or gasket, is cheap to manufacture, and has improved performance over the previous form of tank.

Specifically it is the object of the invention to provide a downwardly opening container, round in cross section, that is composed preferably of plastic and has a lower rounded edge.

A base plate preferably of harder plastic is provided with an inclined round outer rim that receives the edge of the container. On the axis of the container is a tube or pipe that extends through the base and has at its lower end a radial shoulder or abutment that bears against the under side of the base. The pipe has an upper end that terminates adjacent the top of the container and is threadedly attached to the top. Consequently, the joint between the lower edge of the container and rim of the base may be tightened by adjusting the threaded connection. The tube or pipe also serves as a vent between the atmosphere beneath the base and the upper end of the container that may at times serve to relieve the vacuum in the container.

It is a further object of the invention to make the container of a softer plastic than the base material, which preferably also is plastic. It is also an object of the invention to provide the base with embossments and supports that are integral with the base and serve to mount the various valves, central mechanisms, etc., on the base.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of the humidifier and a portion of the pan and furnace.

FIG. 2 is a sectional view taken along the line 2-2 of FIG. 1.

FIG. 3 is an enlarged sectional view taken along line 33 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT The humidifier is normally mounted on a furnace, part of which includes a furnace wall 10. The humidifier has a pan 11, part being retained internally and part externally of the furnace 11, and is supported on the walls 10. A tank base 12 is supported on the pan ll externally of the furnace walls 10 and includes a horizontal base plate 13 with a round peripheral rim 14, the latter being inclined and having an inner inclined sur- 0 face 15. An inverted or downwardly opening container 16 is supported on the base 12, is round in cross section, and has its lower rounded edge 17 engaging the inclined surface 15. As is evident in FIG. 1, the container 16 has a frusto-conical side wall 18 and an integral horizontal top 19, the latter being thicker in its center than at its edges. The side 18, being frustoconical shaped, tends to resist distortion due to compression forces on the top.

The container 16 is held on the base 12 by means of an upright tubular member or pipe 20 located centrally in and along the axis of the container and has a lower end portion projecting through the base plate 13. The pipe 20 has a radial shoulder or abutment 21, formed by crimping the pipe 20, that bears against the under side of the plate 13, there being provided a countersunk opening 22 for the shoulder 21 to bear against. The top of the pipe 20 has an internally threaded plug 23 in its upper end that receives or adjustably connects to a screw 24 seated in a countersunk opening 25 in the top 19. By adjusting the screw 24, the entire container 16 may be drawn tightly down on the base 12 and the joint between edge 17 and the inclined surface 15 may be sealed. The entire tank may be disassembled by removing the screw 24 from the plug 23. The plastic of container 16 is somewhat softer than that of the base 12 to thereby cause edge 17 to shape to and seal against the surface 15. The top end of the pipe 20 has air openings 26 that serve to permit air at times to move into the top of the container and thereby relieve vacuum therein. It should also be recognized that the vacuum normally existing in the tank will normally prevent leaks at the base of the container.

The base 12 has a pair of integral protuberances or embossments 30, 31 projecting upwardly and downwardly respectively from the plate 13. The embossment 30 is hollow and has an internal threaded surface that threadedly receives a valve housing 32, the latter having a fitting 33 connected to a water main 34. The upper side of the embossment 30 has an opening or water inlet 35. Contained within the embossment 30 is a gasket 36 held in place by the upper edge of the valve housing 32. Retained within the housing is a shuttle valve 37 with an upper stem 38 projecting through the inlet 35.

The protuberance 31 has an internal opening 40 that opens into the tank and serves as the water discharge outlet. The

lower edge 41 of the protuberance 31 is beneath the lower edge 42 of the pipe 20.

Also integral with the base 12 is a pair of upwardly projecting fulcrum supports 45, 46 with inwardly facing notches 47, 48 respectively. A lever or plate 50 is bifurcated at one end and rests in the notch 48 of the support 46. The lever 50 extends diametrically across the container 16, there being an opening 51 that receives the pipe 20. The opposite end of lever 50 has a lug 52 on which is piloted one end of a spring 53. The opposite end of the spring 53 is supported on a T- shaped carrier 54, one end of which is bifurcated to rest in the notch 47.

Carried on the lever 50 and above the water outlet 40 is a water discharge valve 56 having an upper vertical stem 57 extending through V the lever 50 and held thereon by a prestretched spring 58 which tends to bias the valve upwardly until the shoulder of the base of stem 57 rests against the lever 50.

A float 60 is provided within the container and moves vertically in accordance with the water level. The float 60 has a central opening 61 that receives the pipe 20 thereby permitting the latter to serve as a vertical guide for the float. The float 60 has a vertical notch 59 adjacent the opening 61 that receives a vertical rod 62, the upper end of which is hooked at 63 over the top of float 60. The lower end of the rod has a slightly inclined offset portion at 64 and is hooked under the lever 50 at 65. A downwardly projecting abutment or lug 66 is provided on the under side of float 60 and is in vertical alignment with the lever 50.

The humidifier operates in the following manner. FIG. 1 shows the tank substantially at its full position in which the level 70 of the water retains the float 60 at the top of the tank. The shuttle or inlet valve 37 is closed and the outlet valve 56 is open. The level 71 of the water in pan 11 is above the lower end 42 of the pipe 20, thereby creating a vacuum in the tank above the water level 70. The vacuum retains the water in the tank.

As the water level 71 lowers, due to evaporation in the pan 11, below the end 42 to thereby relieve the vacuum in the tank, water will pass through the outlet 40 into the pan. As the water level 71 passes over the lower end 42, the vacuum is again established and water will cease to flow through outlet 40. This will continue until the water level 70 is close to the base 12 and the abutment 66 bears on the offset portion 64 which forces the outer end thereof to bear on an outer part of plate 50. This feature is important for the reason that a comparatively small float may be used since the weight thereof will be applied at the end of lever 50 and at its greatest distance from the point of pivot on fulcrum within the notch 48. The water pressure on the valve 37 plus the effect of spring 53 will restrain downward movement of the lever 50 until the lever almost supports the entire weight of the float 60. At this time the lever 50 will snap downward to a lower overcenter position to thereby simultaneously open the inlet valve 37 and close the outlet valve 56. The tank will then automatically begin filling. These latter positions are shown in dotted representation in FIG. 1.

The head or weight of the water on valve 56 will retain the valve 56 closed. As the float rises, it will contact the hook 63 to cause the rod 62 to raise the lever 50. The spring 58 will yield to permit the valve to remain closed until the lever 50 snaps upwardly over center to permit the inlet valve to close and the outlet valve 56 to open slightly. Once water flows under valve 56 the spring 58 then raises the valve to a position as shown in FIG. 1 in which it bears against the lever 50. The spring 58 will retain the valve 56 open until the lever 50 again snaps into its lower overcenter position.

Iclaim:

l. A hermetically sealed tank for use with a furnace humidifier that includes a pan adapted for extension through a furnace wall, the tank comprising: a downwardly opening container having a top and depending sides with a lower continuous edge; a base having an upwardly projecting rim with a peripheral inclined surface adapted to engage the edge of the container, the base further having a water outlet and a water inlet; an upright tubular member centrally located in respect to the container extending through the base and having radial abutment means engaging the lower side of the base and having its upper end adjacent to and with an adjustable attachment to the top of the container whereby the lower edge may be drawn tightly against the rim, the tubular member further having openings at its upper end and within the container and a lower end disposed within the pan; a water service valve at the base inlet; an outlet valve for the base outlet; and mechanical means within the container responsive to move in accordance with the water level and adapted in one movement to close the service valve and open the outlet valve and in a second movement to open the service valve and close the outlet valve.

2. The structure as set forth in claim 1 in which the base includes a horizontally disposed section with an integral vertically disposed embossment, the embossment being hollow and having a threaded surface and the water inlet at its upper side, and the water service valve includes a housing threaded to the embossment and a check valve for closing the water inlet.

3. The structure as set forth in claim 2 in which the check valve has a stem extending through the inlet, the mechanical means includes a lever above the check valve and fulcrummed for vertical movement within the container, the lever being engageable with the stem for moving it vertically, and a float operatively associated with the lever for moving the lever vertically in accordance with the water level.

4. The structure as set forth in claim 3 in which the lever is fulcrummed on an upright support integral with and extending upwardly from the base.

5. The structure as set forth in claim 3 further characterized by the water outlet valve being operatively connected to the lever for retaining the outlet valve open when the inlet valve is closed and for retaining the outlet valve closed when the inlet valve is open.

6. The structure as set forth in claim 5 in which there is provided a spring between the lever and water outlet valve that yields to permit the outlet valve to remain closed and biases the outlet valve toward the open position upon the lever reaching a predetermined height.

7. The structure as set forth in claim 1 in which the outlet is formed by a hollow downwardly projecting protuberance integral with the base and opening upwardly into the container and downwardly at a level beneath the lower end of the tubular member.

8. The structure as set forth in claim 1 in which the base has integral upwardly projecting support means and said mechanical means is supported on the support means.

9. The structure as set forth in claim 1 in which the container is round in cross section with a lower round edge and the rim is also round.

10. The structure as set forth in claim 9 in which the container is frustoconical shaped with its upper end being smaller than its lower round edge.

11. The structure as set forth in claim 9 in which the tubular member is on the axis of the container and the mechanical means includes a circular float with a central opening formed about the tubular member whereby the tubular member serves as a vertical guide for the float.

12. A vacuum water storage tank comprising: a base having an upwardly projecting peripheral rim with an internal inclined wall; a downwardly opening container with a lower edge engaging the inclined wall; an upright pipe centrally located in the container and having a lower portion extending through the base and an open top portion adjacent the top of the container; a radial shoulder rigid with the pipe engaging the underside of the base; a vertically adjustable connection between the top of the container and the pipe for tightening the edge against the inclined surface; a float formed about the pipe and adapted to move vertically in accordance with the level of the water; a water outlet valve; a water inlet valve; and means connecting the water outlet valve and water inlet valve to the float whereby as the float approaches the base it closes the outlet valve and opens the inlet valve and as the float approaches the top it opens the outlet valve and closes the inlet valve.

13. The structure as set forth in claim 12 in which the rim and container are round and the container is frusto-conical shaped.

14. The structure as set forth in claim 12 in which the container and base are of plastic material and the edge of the container is of softer plastic than the material forming said inclined surface. 

